1. Field of the Invention
The present invention relates to a communication originating network and a packet data network through which the communication is transmitted and more particularly, minimizing communications in the packet data network necessary to complete initiation of the communication.
2. Description of the Prior Art
The GSM (global system for mobile communications) utilizes the concept of location area code (LAC) to reduce unnecessary paging messages between a MSC (mobile switching center or mobile services switching center) and a BSC (base station controller). In the GSM system, a mobile terminated call procedure is initiated by the MSC by sending a paging message pursuant to GSM 08.808 Version 5.6.2, 3.2.1.19, to the BSS (base station subsystem) i.e. base station controller. The paging message contains information, including the IMSI (international mobile subscriber identity) or the TMSI (temporary mobile subscriber identity), of the mobile terminal to be paged as well as the so-called cell identifier list pursuant to GSM 08.808, Version 5.6.2, 3.2.2.27. The cell identifier list may contain various types of information describing the target paging area.
FIG. 1 illustrates a prior art system 10 which originates calls in a communication system 12, which is a GSM network including a communication originating entity, which are transmitted through a packet data network 14, which is an IP network, to one of a plurality of radio communication systems 16, which comprise a radio gateway, to one of a plurality of wireless terminals 18 which are part of the GSM network. The communication system 12 includes a MSC 20 and VLR (visiting location register) 22 which functions as a database identifying all wireless terminals 18 which are operational within the area of the communication system 12 under the control of the MSC. The VLR 22 functions to maintain information regarding roaming of the wireless terminals within the communication system 12. Furthermore, a HLR (home location register not illustrated) is used in the GSM system to keep track of where the VLR is maintained in the GSM system, namely the MSC 20 through which calls should be directed to a particular wireless terminal 18. In view of the HLR knowing the VLR""s location in the GSM system, a call directed to a wireless terminal 18 which originates in the communication system 12 may be directed through the MSC 20 and then to the packet data network 14, one or more radio communication systems 16 and to one or more wireless terminals 18.
An originated call generates a paging message which is directed to the MSC 20 and is forwarded to gateway 24 within the packet data network 14 to all of the gatekeepers GK 1002, 1003, 1005, 1006, 1008 and 1009 connected thereto. The gatekeepers GK perform a number of functions including the function of a PBX. The gateway and gatekeepers GK operate in compliance with H.323. The paging message to set up a communication to at least one wireless terminal 18 is further forwarded to each of the radio gateways 16 and is finally forwarded to each of the wireless terminals 18. The radio gateways 16 function as access points to wireless local area networks which are not illustrated and control connectivity of communications forwarded through the packet data network 14 to individual terminals 18.
The location of the individual wireless terminals 18 is automatically updated as a result of the radio communications systems 16 being part of the GSM network 12. Operation of the wireless terminals 18 in the GSM network permits the individual wireless terminals 16 to be located by accessing of information within the VLR 22.
The prior art system of FIG. 1 has the disadvantage of transmitting a paging message to set up an individual communication (e.g. telephone call) which is to be terminated at a wireless terminal 18 through each of the gatekeepers 1002, 1003, 1005, 1006, 1008, and 1009. This paging procedure is highly inefficient because, in effect, every GK connected to gateway 24 must be paged and in turn, every radio communication system 16 must be paged in order to complete the call set up procedure. This results in a significant amount of signalling traffic.
The present invention is a system and a method of initiating a communication which is transmitted by a packet data network containing at least a plurality of gatekeepers and preferably, a gateway coupled to the plurality of gatekeepers to a wireless terminal in one of a plurality of wireless systems. In accordance with the invention, communication initiation messages or paging messages are sent only to one or more gatekeepers within a paging area or LAC in which a wireless terminal to which the communication is directed is known to be located by the packet data network. A location register/directory service, which may be located any where in the packet data network, stores an association between one or more gatekeepers and one or more paging areas or LACs which are identified by processing of the information contained in the communication. Upon receipt of a message from within the packet data network or from an external communication system originating the communication, the packet data network determines from the message or page directed to a gatekeeper or to the gateway, when the communication originates from the external network, a particular paging area or LAC in which the communication initiation message or page is to be transmitted to initiate the communication. The location register/directory service associates the paging area or LAC determined from the communication initiation message or page with one or more gatekeepers to which the communication initiation message or paging message is to be directed which eliminates the problem of the prior art of sending paging messages to all gatekeepers which requires significant signalling traffic for the setting up of communications. As a result, the communication initiation message or paging message is transmitted to one or more gatekeepers which are located within the area determined from the communication initiation message or paging message.
The preferred contents of the location register/directory service of the packet data network contain an identification of each of the gatekeepers located in the packet data network, the gatekeeper""s address (packet data network or IP address) and the association of one or more gatekeepers with one or more paging areas or LACs. This information makes possible the transmission of the communication initiation or paging message to the correct one or more gatekeepers by the processing of the information within the received communication initiation or paging message to identify the paging area or LAC in which the one or more gatekeepers are located to which the communication initiation message or paging message is to be transmitted at the packet data address of the one or more gatekeepers stored therein. The paging area or LAC is a key which locates the address of the particular gatekeeper(s) to which the communication initiation message or paging message is sent. Thereafter, the communication initiation message or paging message is forwarded to one or more radio systems (radio gateways) associated with each gatekeeper to complete the initiation of the communication with the wireless terminal to receive the communication without requiring communications with all of the gatekeepers located in the packet data network.
A method of initiating a communication which is transmitted by a packet data network, containing a gateway and a plurality of gatekeepers coupled to the gateway, to a wireless terminal in one of a plurality of wireless systems in accordance with the invention includes processing information relating to the communication to determine at least area in which the communication is to be broadcast to the wireless terminal; identifying from the at least area at least one associated destination gatekeeper to which a message should be transmitted from the gateway to initiate the communication and to which the communication is transmitted; transmitting the message from the gateway to the at least one associated destination gatekeeper; and transmitting the message from the at least one associated destination gatekeeper to at least one of the plurality of wireless systems. A single gatekeeper may be associated with an area and the message may be transmitted from the gateway to each single gatekeeper associated with each identified at least one area; a single gatekeeper may be associated with a plurality of areas and the message may be transmitted from the gateway to the single gatekeeper associated with the identified plurality of areas; or a plurality of gatekeepers may be associated with a single area and the message may be transmitted from the gateway to the plurality of destination gatekeepers associated with the single area. The communication may originate in a telecommunication network and may be transmitted to the packet data network through the gateway. Each of the wireless systems may comprise a radio access point and a plurality of wireless terminals. The packet data network may include a database which stores information related to each of the plurality of gatekeepers including the association between gatekeepers and areas; and wherein the determination of the at least one destination gatekeeper to which the message is to be transmitted from the gateway may be performed by processing the communication and using the information obtained from the processing to locate the at least one area stored in the database and identifying the at least one destination gatekeeper to which the message is transmitted from the located at least one location area. The stored information further may comprise an address of the at least one destination gatekeeper in the packet data network to which the message is transmitted from the gateway. The telecommunication network may be a cellular network. The wireless terminal may be mobile between areas and the database may be updated with a current area when the mobile terminal moves into a new area which permits the message to be directed to the gatekeeper associated with the area in which mobile terminal is currently located. The communication may originate in a telecommunication network and may be transmitted to the packet data network through the gateway; the mobile terminal may be a terminal in the telecommunication network.
A system in accordance with the invention includes a packet data network including a gateway and a plurality of gatekeepers coupled thereto; a plurality of wireless systems; a plurality of wireless terminals; and a location database which stores at least one area, the at least one area being associated with at least one gatekeeper to which messages are transmitted to initiate a communication and to which the communication is transmitted; and wherein the packet data network processes information within the communication which is directed to at least one of the plurality of wireless terminals and determines at least one area to which a message is to be transmitted to initiate the communication and uses the database to identify from the at least one area at least one destination gatekeeper to which the message is transmitted from the gateway and transmits the message from the gateway to the at least destination gatekeeper and from the at least one destination gatekeeper to at least one of the plurality of wireless systems. A single gatekeeper may be associated with an area and the message is transmitted from the gateway to each single gatekeeper associated with each identified at least one area; a single gatekeeper may be associated with a plurality of areas and the message is transmitted from the gateway to the single gatekeeper associated with the identified plurality of areas; or a plurality of gatekeepers may be associated with a single area and the message is transmitted from the gateway to the plurality of destination gatekeepers associated with the single area. A telecommunication network, coupled to the gateway, may originate and transmit the communication to the gateway. The wireless system may comprise a radio access point. The telecommunication network may comprise a cellular network which maintains a database of areas of the plurality of wireless terminals in the telecommunication network; and wherein the location database obtains the areas stored therein from the database of the telecommunications network. The wireless terminal may be mobile between areas and the database may be updated with a current area when the mobile terminal moves into a new area which permits the message to be directed to the gatekeeper associated with the area in which mobile terminal is currently located. The wireless terminal may be mobile between areas and the database may be updated with a current area when the mobile terminal moves into a new area which permits the message to be directed to the gatekeeper associated with the area in which mobile terminal is currently located.
A method of initiating a communication which is transmitted by a packet data network, containing and a plurality of gatekeepers, to a wireless terminal in one of a plurality of wireless systems includes processing information relating to the communication to determine at least one area in which the communication is to be broadcast to the wireless terminal; identifying from the at least one area at least one associated destination gatekeeper to which a message should be transmitted to initiate the communication and to which the communication is transmitted; transmitting the message to the at least one associated destination gatekeeper; and transmitting the message from the at least one associated destination gatekeeper to at least one of the plurality of wireless systems. A single gatekeeper may be associated with a single area and the message may be transmitted to each single gatekeeper associated with each identified at least one area; a single gatekeeper may be associated with a plurality of areas and the page is transmitted to the single gatekeeper associated with the identified plurality of areas; or a plurality of gatekeepers may be associated with a single area and the message may be transmitted to the plurality of destination gatekeepers associated with the single area. Each of the wireless systems comprises a radio access point and a plurality of wireless terminals. The packet data network includes a database which stores information related to each of the plurality of gatekeepers including the association between gatekeepers and areas; and wherein the determination of the at least one destination gatekeeper to which the message is to be transmitted is performed by processing the communication and using the information obtained from the processing to locate the at least one area stored in the database and identifying the at least one destination gatekeeper to which the message is transmitted. The stored information further may comprise an address of the at least one destination gatekeeper in the packet data network to which the message is transmitted from another gatekeeper.
A system in accordance with the invention includes a packet data network including a plurality of gatekeepers coupled thereto; a plurality of wireless systems; a plurality of wireless terminals; and a location database which stores at least one area, the at least one area being associated with at least one gatekeeper to which messages are transmitted to initiate a communication and to which the communication is transmitted; and wherein the packet data network processes information within the communication which is directed to at least one of the plurality of wireless terminals and determines at least one area to which a message is to be transmitted to initiate the communication and uses the database to identify from the at least one area at least one destination gatekeeper to which the message is transmitted and transmits the message to the at least destination gatekeeper and from the at least one destination gatekeeper to at least one of the plurality of wireless systems. A single gatekeeper may be associated with a plurality of areas and the message may be transmitted from the gateway to the single gatekeeper associated with the identified plurality of areas. The wireless system may comprise a radio access point. The wireless terminal may be mobile between areas and the database may be updated with a current area when the mobile terminal moves into a new area which permits the message to be directed to the gatekeeper associated with the area in which mobile terminal is currently located.